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The interplay between the marine diazotroph Vibrio diazotrophicus and its prophage shapes both biofilm structure and nitrogen release
No full textInternational audienceABSTRACT Marine environments are frequently oligotrophic, characterized by low amount of bioassimilable nitrogen sources. At the global scale, the microbial fixation of N₂, or diazotrophy, represents the primary source of fixed nitrogen in pelagic marine ecosystems, playing a key role in supporting primary production and driving the export of organic matter to the deep ocean. However, given the high energetic cost of N₂ fixation, the active release of fixed nitrogen by diazotrophs appears counterintuitive, suggesting the existence of alternative passive release pathways that remain understudied to date. Here, we show that the marine non-cyanobacterial diazotroph Vibrio diazotrophicus is endowed with a prophage belonging to the Myoviridae family, whose expression is induced under anoxic and biofilm-forming conditions. We demonstrate that this prophage can spontaneously excise from the genome of its host and that it forms intact and infective phage particles. Moreover, phage-mediated host cell lysis leads to increased biofilm production compared with a prophage-free derivative mutant and to increased release of dissolved organic carbon and ammonium. Altogether, the results suggest that viruses may play a previously unrecognized role in oceanic ecosystem dynamics by structuring microhabitats suitable for diazotrophy and by contributing to the recycling of (in)organic matter. IMPORTANCE Diazotrophs are key players in ocean functioning by providing fixed nitrogen to ecosystems and fueling primary production. However, from a physiological point of view, the active release of nitrogenous compounds by diazotrophs is paradoxical, since they would invest in an energy-intensive process and supply nutrient to non-sibling cells, with the risk of being outcompeted. Therefore, alternative ways leading to the release of fixed nitrogen must exist. Here, we show that the marine non-cyanobacterial diazotroph Vibrio diazotrophicus possesses one prophage, whose activation leads to cell death, increased biofilm production, and the release of dissolved organic compounds and ammonium. Taken together, our results provide evidence that marine phage–diazotroph interplay leads to the creation of microhabitats suitable for diazotrophy, such as biofilm, and to nutrient cycling, and contributes to better understanding of the role of viruses in marine ecosystems
Becoming a parent, changing eating habits. The evolution of parental roles
No full textInternational audienceThe aim of the study is to identify periods of dietary changeduring parenthood. Five phases of a parental dietary journey have beenidentified, highlighting the distinct roles played by parents at each stage ofthe parental journey, the markers of transition, and the periods when healthyeating is a key phase in fulfilling their protective, motivational, andeducational roles
Bridging practice theory and behavioral science to understand and strengthen recyclable waste sorting in collective housing
No full textInternational audiencePurpose Despite their environmental and economic importance, recycling rates remain low in collective housing. Public policies grounded in decontextualized psychological mechanisms show limited effectiveness in this setting. By contrast, practice-based research shifts attention to contextualized everyday routines but offers few operational pathways for intervention. This study aims to advance a more integrated perspective by examining how psychological mechanisms are activated, inhibited or reshaped by collective housing through residential elements of materiality, meanings and competences. Design/methodology/approach Twenty-two semi-structured interviews were conducted with residents living in collective housing in Paris and the surrounding departments. Psychological mechanisms were explored in depth through the practice elements of materiality, meanings and competences. Findings The results show that the residential context deeply shapes how individuals engage with waste sorting. Affordances and emotions elicited by shared spaces profoundly shape sorting practices. Residents actively reconstruct residential sorting norms and cooperation expectations, and experience shame, guilt and pride tied to recycling. Competences extend beyond the household, shaping how residents navigate shared spaces, communicate with neighbors and restore order within the residence. Research limitations/implications Future research should further examine how residential context shapes consumption practices within a systemic perspective. Observational methods, such as sensor data or resident-generated video, could help identify key change points in daily routines. Experimental designs could test residential mechanisms, such as how residential altruistic acts shape waste-sorting behavior. Finally, specialized tools like causal loop diagrams may support a systemic approach to the dynamics of social and consumption change. Practical implications This study offers a framework for field diagnostics and context-based interventions that target the residential environment rather than individuals, focusing on residential psychological mechanisms. Originality/value From a critical realist perspective, collective housing is not simply a constraint on change but a generative structure that shapes waste-sorting routines by activating and shaping residential psychological mechanisms
Functional Performance Tests Following Unilateral Total Knee Arthroplasty: Protocol for a Scoping Review
No full textInternational audienceAims: To outline a protocol for a scoping review that will systematically map and synthesize the literature on the use of the 6-Minute Walk Test (6MWT), 2-Minute Walk Test (2MWT), Timed Up and Go (TUG) test, and other standardized walk tests for assessing functional performance in patients following unilateral Total Knee Arthroplasty (TKA). Study Design: Scoping review protocol. Place and Duration of Study: Not applicable (Literature review protocol). Methodology: This scoping review will be conducted following the Joanna Briggs Institute (JBI) methodology and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). A comprehensive search will be performed in PubMed (MEDLINE), Embase, Scopus, Web of Science, and PEDro databases, supplemented by a grey literature search. Two independent reviewers will screen studies for eligibility, extract data, and chart the results. The Population, Concept, and Context (PCC) framework will guide eligibility: adults with unilateral TKA (Population), use of 6MWT, 2MWT, TUG, or standardized walk tests (Concept), in a post-operative. Results: This is a protocol study; no results are presented at this stage. Conclusion: The findings from this review are expected to identify the extent and nature of the evidence on functional performance tests in the unilateral TKA population. We anticipate this work will highlight variations in testing protocols, identify research gaps, and provide a foundation for standardizing assessment methods, which is essential for improving the synthesis of clinical trial data and guiding evidence-based rehabilitation practices
La Dama de Elche: cómo nace un icono
No full textInternational audienceDiscovered in August 1897, the Lady of Elche quickly became a genuine symbol of Iberian art, supplanting the ex-votos from the Cerro de los Santos that had previously attracted the attention of the academic community, in particular the Great Lady Offerant. We propose to review the process by which the bust of the Alcudia of Elche became an icon of Iberian art, focusing on three main factors: firstly, the role played by the communication strategy implemented by Léon Heuzey and Pierre Paris in the months following its discovery; secondly, its rapid exhibition in the Louvre, which gave the sculpture and the art to which it belongs unprecedented visibility and legitimacy; and thirdly, Pierre Paris's account of its discovery and purchase, a novelistic discourse in which the facts blend with personal emotions tinged with mysticism.Descubierta en agosto de 1897, la Dama de Elche se impuso rápidamente como un icono representativo del arte ibérico, desplazando a los exvotos del Cerro de los Santos que hasta entonces habían atraído la atención de la comunidad científica, en particular la Gran Dama Oferente. Nos proponemos repasar las etapas que llevaron a que el busto de la Alcudia de Elche se convirtiera en un icono del arte ibérico, centrándonos en tres factores principales: en primer lugar, el papel desempeñado por la verdadera estrategia de comunicación puesta en marcha por Léon Heuzey y Pierre Paris en los meses que siguieron a su descubrimiento; en segundo lugar, su rápida exposición en el Louvre, que dio a la escultura y al arte al que pertenece una visibilidad y una legitimidad sin precedentes; y, por último, el relato de Pierre Paris sobre su descubrimiento y su compra, un discurso novelesco en el que los hechos se mezclan con emociones personales teñidas de misticismo.Découverte en août 1897, la Dame d’Elche s’est rapidement imposée comme un véritable symbole de l’art ibérique, supplantant les ex-voto du Cerro de los Santos qui avaient jusqu’à cette date retenu l’attention de la communauté scientifique, en particulier la Grande Dame Offrante. Nous nous proposons de revenir sur les étapes qui ont fait du buste de l’Alcudia d’Elche une icône de l’art ibérique en insistant sur trois facteurs principaux : d’une part, le rôle joué par la véritable stratégie de communication mise en œuvre par Léon Heuzey et Pierre Paris dans les mois qui suivent sa découverte ; d’autre part, sa rapide exposition au Louvre qui donne à la sculpture et à l’art auquel elle se rattache une visibilité et une légitimité inédites ; enfin, le récit de sa découverte et de son achat élaboré par Pierre Paris, un discours romanesque dans lequel les faits se mêlent à des émotions personnelles teintées de mysticisme
Improving Multimodal Distillation for 3D Semantic Segmentation under Domain Shift
No full textInternational audienceSemantic segmentation networks trained under full supervision for one type of lidar fail to generalize to unseen lidars without intervention. To reduce the performance gap under domain shifts, a recent trend is to leverage vision foundation models (VFMs) providing robust features across domains. In this work, we conduct an exhaustive study to identify recipes for exploiting VFMs in unsupervised domain adaptation for semantic segmentation of lidar point clouds. Building upon unsupervised image-to-lidar knowledge distillation, our study reveals that: (1) the architecture of the lidar backbone is key to maximize the generalization performance on a target domain; (2) it is possible to pretrain a single backbone once and for all, and use it to address many domain shifts; (3) best results are obtained by keeping the pretrained backbone frozen and training an MLP head for semantic segmentation. The resulting pipeline achieves state-of-the-art results in four widely-recognized and challenging settings. The code will be available at: github.com/valeoai/muddos
Le sex appeal des castrats italiens. Sexualité non reproductive et masculinités dans la France des Lumières
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Unpacking the dynamic role of physical effort in shaping behavior
No full textInternational audienceEffort plays a crucial role in shaping behavior. We propose that physical effort - and its perception - modulates people's engagement across different stages of behavioral regulation: before, during, and after engagement. We demonstrate that individuals tend to avoid effort before engagement, minimize effort during task performance, and derive a sense of reward from effort after engagement due to an effort-justification mechanism. This dynamic and stage-specific approach moves beyond static models of effort (de)valuation, offering a more nuanced understanding of how effort shapes behavior. Focusing on physical activity, we explore how these specific effort-related mechanisms could promote physical activity by fostering conditions where individuals engage in active behaviors because of the potential rewards effort brings, despite its associated cost
Soigner et contraindre : regards civiques sur la folie masculine
No full textInternational audienceMadness modifies the individual, his corporeality and his personality and changes his identity in the others’ eyes. The body is challenged in its physical and mental capacities, even intellectual, but also in its performativity. The family, the doctors and the city try to restrain and keep the madman at a distance, to protect him and to protect themselves from his unreasonable acts. Because he disturbs the social order and reveals the dysfunctions of the city. His vulnerability is then a mirror of the fears of the community: the transgression of norms and the weakening of social and political links.La locura altera al individuo, su cuerpo y su personalidad, y cambia su identidad a los ojos de los demás. Las capacidades físicas, mentales e incluso intelectuales del cuerpo se ven desafiadas, al igual que su performatividad. La familia, los médicos y la ciudad intentan contener y mantener a distancia al loco, para protegerle y protegerse de sus actos irracionales. El loco perturba el orden social y revela las disfunciones de la ciudad. La vulnerabilidad de un individuo refleja los temores de la comunidad: la transgresión de las normas y el debilitamiento de los lazos sociales y políticos.La folie modifie l’individu, sa corporéité et sa personnalité et change son identité aux yeux des autres. Le corps est mis à mal dans ses capacités physiques et mentales, voire intellectuelles, mais aussi dans sa performativité. La famille, les médecins et la cité tentent de contraindre et de tenir à distance le fou, pour le protéger, pour se protéger de ses actes déraisonnés. Car il perturbe l’ordre social et révèle les dysfonctionnements de la cité. La vulnérabilité d’un individu est alors un miroir des craintes de la communauté : la transgression des normes et la fragilisation des liens sociaux et politiques